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path: root/drivers/cpuidle
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2013-08-30cpuidle: coupled: abort idle if pokes are pendingColin Cross1-25/+82
Joseph Lo <josephl@nvidia.com> reported a lockup on Tegra20 caused by a race condition in coupled cpuidle. When two or more cpus enter idle at the same time, the first cpus to arrive may go to the ready loop without processing pending pokes from the last cpu to arrive. This patch adds a check for pending pokes once all cpus have been synchronized in the ready loop and resets the coupled state and retries if any cpus failed to handle their pending poke. Retrying on all cpus may trigger the same issue again, so this patch also adds a check to ensure that each cpu has received at least one poke between when it enters the waiting loop and when it moves on to the ready loop. Reported-and-tested-by: Joseph Lo <josephl@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Colin Cross <ccross@android.com> Cc: 3.6+ <stable@vger.kernel.org> # 3.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-30cpuidle: coupled: disable interrupts after entering safe stateColin Cross1-0/+2
Calling cpuidle_enter_state is expected to return with interrupts enabled, but interrupts must be disabled before starting the ready loop synchronization stage. Call local_irq_disable after each call to cpuidle_enter_state for the safe state. Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Change struct menu_device field typesTuukka Tikkanen1-11/+17
Field predicted_us value can never exceed expected_us value, but it has a potentially larger type. As there is no need for additional 32 bits of zeroes on 32 bit plaforms, change the type of predicted_us to match the type of expected_us. Field correction_factor is used to store a value that cannot exceed the product of RESOLUTION and DECAY (default 1024*8 = 8192). The constants cannot in practice be incremented to such values, that they'd overflow unsigned int even on 32 bit systems, so the type is changed to avoid unnecessary 64 bit arithmetic on 32 bit systems. One multiplication of (now) 32 bit values needs an added cast to avoid truncation of the result and has been added. In order to avoid another multiplication from 32 bit domain to 64 bit domain, the new correction_factor calculation has been changed from new = old * (DECAY-1) / DECAY to new = old - old / DECAY, which with infinite precision would yeild exactly the same result, but now changes the direction of rounding. The impact is not significant as the maximum accumulated difference cannot exceed the value of DECAY, which is relatively small compared to product of RESOLUTION and DECAY (8 / 8192). Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Add a comment warning about possible overflowTuukka Tikkanen1-0/+9
The menu governor has a number of tunable constants that may be changed in the source. If certain combination of values are chosen, an overflow is possible when the correction_factor is being recalculated. This patch adds a warning regarding this possibility and describes the change needed for fixing the issue. The change should not be permanently enabled, as it will hurt performance when it is not needed. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Fix variable domains in get_typical_interval()Tuukka Tikkanen1-6/+9
The menu governor uses a static function get_typical_interval() to try to detect a repeating pattern of wakeups. The previous interval durations are stored as an array of unsigned ints, but the arithmetic in the function is performed exclusively as 64 bit values, even when the value stored in a variable is known not to exceed unsigned int, which may be smaller and more efficient on some platforms. This patch changes the types of varibles used to store some intermediates, the maximum and and the cutoff threshold to unsigned ints. Average and standard deviation are still treated as 64 bit values, even when the values are known to be within the domain of unsigned int, to avoid casts to ensure correct integer promotion for arithmetic operations. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Fix menu_device->intervals typeTuukka Tikkanen1-1/+1
Struct menu_device member intervals is declared as u32, but the value stored is (unsigned) int. The type is changed to match the value being stored. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: CodingStyle: Break up multiple assignments on single lineTuukka Tikkanen1-3/+6
The function get_typical_interval() initializes a number of variables that are immediately after declarations assigned constant values. In addition, there are multiple assignments on a single line, which is explicitly forbidden by Documentation/CodingStyle. This patch removes redundant initial values for the variables and breaks up the multiple assignment line. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Check called function parameter in get_typical_interval()Tuukka Tikkanen1-5/+13
get_typical_interval() uses int_sqrt() in calculation of standard deviation. The formal parameter of int_sqrt() is unsigned long, which may on some platforms be smaller than the 64 bit unsigned integer used as the actual parameter. The overflow can occur frequently when actual idle period lengths are in hundreds of milliseconds. This patch adds a check for such overflow and rejects the candidate average when an overflow would occur. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Rearrange code and comments in get_typical_interval()Tuukka Tikkanen1-13/+15
This patch rearranges a if-return-elsif-goto-fi-return sequence into if-return-fi-if-return-fi-goto sequence. The functionality remains the same. Also, a lengthy comment that did not describe the functionality in the order it occurs is split into half and top half is moved closer to actual implementation it describes. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23cpuidle: Ignore interval prediction result when timer is shorterTuukka Tikkanen1-1/+4
This patch prevents cpuidle menu governor from using repeating interval prediction result if the idle period predicted is longer than the one allowed by shortest running timer. Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-15cpuidle-kirkwood.c: simplify use of devm_ioremap_resource()Julia Lawall1-3/+0
Remove unneeded error handling on the result of a call to platform_get_resource when the value is passed to devm_ioremap_resource(). A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,n,e,e1; expression ret != 0; identifier l; @@ - res = platform_get_resource(pdev, IORESOURCE_MEM, n); ... when != res - if (res == NULL) { ... \(goto l;\|return ret;\) } ... when != res + res = platform_get_resource(pdev, IORESOURCE_MEM, n); e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-15Merge branch 'cpuidle/arm-next' of ↵Rafael J. Wysocki2-2/+2
git://git.linaro.org/people/dlezcano/linux into pm-cpuidle Pull ARM cpuidle updates from Daniel Lezcano. * 'cpuidle/arm-next' of git://git.linaro.org/people/dlezcano/linux: cpuidle: kirkwood: Make kirkwood_cpuidle_remove function static cpuidle: calxeda: Add missing __iomem annotation SH: cpuidle: Add missing parameter for cpuidle_register()
2013-08-15Merge back earlier 'pm-cpuidle' material.Rafael J. Wysocki8-110/+298
2013-08-12cpuidle: kirkwood: Make kirkwood_cpuidle_remove function staticJingoo Han1-1/+1
This local symbol is used only in this file. Fix the following sparse warnings: drivers/cpuidle/cpuidle-kirkwood.c:73:5: warning: symbol 'kirkwood_cpuidle_remove' was not declared. Should it be static ? Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-08-12cpuidle: calxeda: Add missing __iomem annotationJingoo Han1-1/+1
Added missing __iomem annotation in order to fix the following sparse warnings: drivers/cpuidle/cpuidle-calxeda.c:44:24: warning: incorrect type in argument 1 (different address spaces) drivers/cpuidle/cpuidle-calxeda.c:44:24: expected void [noderef] <asn:2>*<noident> drivers/cpuidle/cpuidle-calxeda.c:44:24: got void *extern [addressable] [toplevel] scu_base_addr drivers/cpuidle/cpuidle-calxeda.c:56:24: warning: incorrect type in argument 1 (different address spaces) drivers/cpuidle/cpuidle-calxeda.c:56:24: expected void [noderef] <asn:2>*<noident> drivers/cpuidle/cpuidle-calxeda.c:56:24: got void *extern [addressable] [toplevel] scu_base_addr Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-29Revert "cpuidle: Quickly notice prediction failure for repeat mode"Rafael J. Wysocki1-69/+4
Revert commit 69a37bea (cpuidle: Quickly notice prediction failure for repeat mode), because it has been identified as the source of a significant performance regression in v3.8 and later as explained by Jeremy Eder: We believe we've identified a particular commit to the cpuidle code that seems to be impacting performance of variety of workloads. The simplest way to reproduce is using netperf TCP_RR test, so we're using that, on a pair of Sandy Bridge based servers. We also have data from a large database setup where performance is also measurably/positively impacted, though that test data isn't easily share-able. Included below are test results from 3 test kernels: kernel reverts ----------------------------------------------------------- 1) vanilla upstream (no reverts) 2) perfteam2 reverts e11538d1f03914eb92af5a1a378375c05ae8520c 3) test reverts 69a37beabf1f0a6705c08e879bdd5d82ff6486c4 e11538d1f03914eb92af5a1a378375c05ae8520c In summary, netperf TCP_RR numbers improve by approximately 4% after reverting 69a37beabf1f0a6705c08e879bdd5d82ff6486c4. When 69a37beabf1f0a6705c08e879bdd5d82ff6486c4 is included, C0 residency never seems to get above 40%. Taking that patch out gets C0 near 100% quite often, and performance increases. The below data are histograms representing the %c0 residency @ 1-second sample rates (using turbostat), while under netperf test. - If you look at the first 4 histograms, you can see %c0 residency almost entirely in the 30,40% bin. - The last pair, which reverts 69a37beabf1f0a6705c08e879bdd5d82ff6486c4, shows %c0 in the 80,90,100% bins. Below each kernel name are netperf TCP_RR trans/s numbers for the particular kernel that can be disclosed publicly, comparing the 3 test kernels. We ran a 4th test with the vanilla kernel where we've also set /dev/cpu_dma_latency=0 to show overall impact boosting single-threaded TCP_RR performance over 11% above baseline. 3.10-rc2 vanilla RX + c0 lock (/dev/cpu_dma_latency=0): TCP_RR trans/s 54323.78 ----------------------------------------------------------- 3.10-rc2 vanilla RX (no reverts) TCP_RR trans/s 48192.47 Receiver %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 59]: *********************************************************** 40.0000 - 50.0000 [ 1]: * 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: Sender %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 11]: *********** 40.0000 - 50.0000 [ 49]: ************************************************* 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: ----------------------------------------------------------- 3.10-rc2 perfteam2 RX (reverts commit e11538d1f03914eb92af5a1a378375c05ae8520c) TCP_RR trans/s 49698.69 Receiver %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 1]: * 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 59]: *********************************************************** 40.0000 - 50.0000 [ 0]: 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: Sender %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 2]: ** 40.0000 - 50.0000 [ 58]: ********************************************************** 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 0]: ----------------------------------------------------------- 3.10-rc2 test RX (reverts 69a37beabf1f0a6705c08e879bdd5d82ff6486c4 and e11538d1f03914eb92af5a1a378375c05ae8520c) TCP_RR trans/s 47766.95 Receiver %c0 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 1]: * 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 27]: *************************** 40.0000 - 50.0000 [ 2]: ** 50.0000 - 60.0000 [ 0]: 60.0000 - 70.0000 [ 2]: ** 70.0000 - 80.0000 [ 0]: 80.0000 - 90.0000 [ 0]: 90.0000 - 100.0000 [ 28]: **************************** Sender: 0.0000 - 10.0000 [ 1]: * 10.0000 - 20.0000 [ 0]: 20.0000 - 30.0000 [ 0]: 30.0000 - 40.0000 [ 11]: *********** 40.0000 - 50.0000 [ 0]: 50.0000 - 60.0000 [ 1]: * 60.0000 - 70.0000 [ 0]: 70.0000 - 80.0000 [ 3]: *** 80.0000 - 90.0000 [ 7]: ******* 90.0000 - 100.0000 [ 38]: ************************************** These results demonstrate gaining back the tendency of the CPU to stay in more responsive, performant C-states (and thus yield measurably better performance), by reverting commit 69a37beabf1f0a6705c08e879bdd5d82ff6486c4. Requested-by: Jeremy Eder <jeder@redhat.com> Tested-by: Len Brown <len.brown@intel.com> Cc: 3.8+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-29Revert "cpuidle: Quickly notice prediction failure in general case"Rafael J. Wysocki1-34/+1
Revert commit e11538d1 (cpuidle: Quickly notice prediction failure in general case), since it depends on commit 69a37be (cpuidle: Quickly notice prediction failure for repeat mode) that has been identified as the source of a significant performance regression in v3.8 and later. Requested-by: Jeremy Eder <jeder@redhat.com> Tested-by: Len Brown <len.brown@intel.com> Cc: 3.8+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-27Merge branch 'cpuidle-arm' into pm-cpuidleRafael J. Wysocki4-16/+173
* cpuidle-arm: ARM: ux500: cpuidle: Move ux500 cpuidle driver to drivers/cpuidle ARM: ux500: cpuidle: Remove pointless include ARM: ux500: cpuidle: Instantiate the driver from platform device ARM: davinci: cpuidle: Fix target residency cpuidle: Add Kconfig.arm and move calxeda, kirkwood and zynq
2013-07-27ARM: ux500: cpuidle: Move ux500 cpuidle driver to drivers/cpuidleDaniel Lezcano3-0/+140
There is no more dependency with arch/arm headers, so we can safely move the driver to the drivers/cpuidle directory. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-27cpuidle: Add Kconfig.arm and move calxeda, kirkwood and zynqSahara3-16/+33
Add Kconfig.arm for ARM cpuidle drivers and moves calxeda, kirkwood and zynq to Kconfig.arm. Like in the cpufreq menu, "CPU Idle" menu is added to drivers/cpuidle/Kconfig. Signed-off-by: Sahara <keun-o.park@windriver.com>
2013-07-15cpuidle: Check if device is already registeredDaniel Lezcano1-1/+4
Make __cpuidle_register_device() check whether or not the device has been registered already and return -EBUSY immediately if that's the case. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Introduce __cpuidle_device_init()Daniel Lezcano1-7/+13
Add __cpuidle_device_init() for initializing the cpuidle_device structure. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Introduce __cpuidle_unregister_device()Daniel Lezcano1-30/+32
To reduce code duplication related to the unregistration of cpuidle devices, introduce __cpuidle_unregister_device() and move all of the unregistration code to that function. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Make cpuidle's sysfs directory dynamically allocatedDaniel Lezcano1-15/+48
The cpuidle sysfs code is designed to have a single instance of per CPU cpuidle directory. It is not possible to remove the sysfs entry and create it again. This is not a problem with the current code but future changes will add CPU hotplug support to enable/disable the device, so it will need to remove the sysfs entry like other subsystems do. That won't be possible without this change, because the kobj is a static object which can't be reused for kobj_init_and_add(). Add cpuidle_device_kobj to be allocated dynamically when adding/removing a sysfs entry which is consistent with the other cpuidle's sysfs entries. An added benefit is that the sysfs code is now more self-contained and the includes needed for sysfs can be moved from cpuidle.h directly into sysfs.c so as to reduce the total number of headers dragged along with cpuidle.h. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Fix white space to follow CodingStyleDaniel Lezcano1-16/+22
Fix white space in the cpuidle code to follow the rules described in CodingStyle. No changes in behavior should result from this. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Check cpuidle_enable_device() return valueDaniel Lezcano1-8/+9
We previously changed the ordering of the cpuidle framework initialization so that the governors are registered before the drivers which can register their devices right from the start. Now, we can safely remove the __cpuidle_register_device() call hack in cpuidle_enable_device() and check if the driver has been registered before enabling it. Then, cpuidle_register_device() can consistently check the cpuidle_enable_device() return value when enabling the device. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15cpuidle: Make it clear that governors cannot be modulesDaniel Lezcano2-22/+2
cpufreq governors are defined as modules in the code, but the Kconfig options do not allow them to be built as modules. This is not really a problem, but the cpuidle init ordering is: the cpuidle init functions (framework and driver) and then the governors. That leads to some weirdness in the cpuidle framework. Namely, cpuidle_register_device() calls cpuidle_enable_device() which fails at the first attempt, because governors have not been registered yet. When a governor is registered, the framework calls cpuidle_enable_device() again which runs __cpuidle_register_device() only then. Of course, for that to work, the cpuidle_enable_device() return value has to be ignored by cpuidle_register_device(). Instead of having this cyclic call graph and relying on a positive side effects of the hackish back and forth cpuidle_enable_device() calls it is better to fix the cpuidle init ordering. To that end, replace the module init code with postcore_initcall() so we have: * cpuidle framework : core_initcall * cpuidle governors : postcore_initcall * cpuidle drivers : device_initcall and remove the corresponding module exit code as it is dead anyway (governors can't be built as modules). [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-04Merge tag 'pm+acpi-3.11-rc1' of ↵Linus Torvalds5-132/+307
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI updates from Rafael Wysocki: "This time the total number of ACPI commits is slightly greater than the number of cpufreq commits, but Viresh Kumar (who works on cpufreq) remains the most active patch submitter. To me, the most significant change is the addition of offline/online device operations to the driver core (with the Greg's blessing) and the related modifications of the ACPI core hotplug code. Next are the freezer updates from Colin Cross that should make the freezing of tasks a bit less heavy weight. We also have a couple of regression fixes, a number of fixes for issues that have not been identified as regressions, two new drivers and a bunch of cleanups all over. Highlights: - Hotplug changes to support graceful hot-removal failures. It sometimes is necessary to fail device hot-removal operations gracefully if they cannot be carried out completely. For example, if memory from a memory module being hot-removed has been allocated for the kernel's own use and cannot be moved elsewhere, it's desirable to fail the hot-removal operation in a graceful way rather than to crash the kernel, but currenty a success or a kernel crash are the only possible outcomes of an attempted memory hot-removal. Needless to say, that is not a very attractive alternative and it had to be addressed. However, in order to make it work for memory, I first had to make it work for CPUs and for this purpose I needed to modify the ACPI processor driver. It's been split into two parts, a resident one handling the low-level initialization/cleanup and a modular one playing the actual driver's role (but it binds to the CPU system device objects rather than to the ACPI device objects representing processors). That's been sort of like a live brain surgery on a patient who's riding a bike. So this is a little scary, but since we found and fixed a couple of regressions it caused to happen during the early linux-next testing (a month ago), nobody has complained. As a bonus we remove some duplicated ACPI hotplug code, because the ACPI-based CPU hotplug is now going to use the common ACPI hotplug code. - Lighter weight freezing of tasks. These changes from Colin Cross and Mandeep Singh Baines are targeted at making the freezing of tasks a bit less heavy weight operation. They reduce the number of tasks woken up every time during the freezing, by using the observation that the freezer simply doesn't need to wake up some of them and wait for them all to call refrigerator(). The time needed for the freezer to decide to report a failure is reduced too. Also reintroduced is the check causing a lockdep warining to trigger when try_to_freeze() is called with locks held (which is generally unsafe and shouldn't happen). - cpufreq updates First off, a commit from Srivatsa S Bhat fixes a resume regression introduced during the 3.10 cycle causing some cpufreq sysfs attributes to return wrong values to user space after resume. The fix is kind of fresh, but also it's pretty obvious once Srivatsa has identified the root cause. Second, we have a new freqdomain_cpus sysfs attribute for the acpi-cpufreq driver to provide information previously available via related_cpus. From Lan Tianyu. Finally, we fix a number of issues, mostly related to the CPUFREQ_POSTCHANGE notifier and cpufreq Kconfig options and clean up some code. The majority of changes from Viresh Kumar with bits from Jacob Shin, Heiko Stübner, Xiaoguang Chen, Ezequiel Garcia, Arnd Bergmann, and Tang Yuantian. - ACPICA update A usual bunch of updates from the ACPICA upstream. During the 3.4 cycle we introduced support for ACPI 5 extended sleep registers, but they are only supposed to be used if the HW-reduced mode bit is set in the FADT flags and the code attempted to use them without checking that bit. That caused suspend/resume regressions to happen on some systems. Fix from Lv Zheng causes those registers to be used only if the HW-reduced mode bit is set. Apart from this some other ACPICA bugs are fixed and code cleanups are made by Bob Moore, Tomasz Nowicki, Lv Zheng, Chao Guan, and Zhang Rui. - cpuidle updates New driver for Xilinx Zynq processors is added by Michal Simek. Multidriver support simplification, addition of some missing kerneldoc comments and Kconfig-related fixes come from Daniel Lezcano. - ACPI power management updates Changes to make suspend/resume work correctly in Xen guests from Konrad Rzeszutek Wilk, sparse warning fix from Fengguang Wu and cleanups and fixes of the ACPI device power state selection routine. - ACPI documentation updates Some previously missing pieces of ACPI documentation are added by Lv Zheng and Aaron Lu (hopefully, that will help people to uderstand how the ACPI subsystem works) and one outdated doc is updated by Hanjun Guo. - Assorted ACPI updates We finally nailed down the IA-64 issue that was the reason for reverting commit 9f29ab11ddbf ("ACPI / scan: do not match drivers against objects having scan handlers"), so we can fix it and move the ACPI scan handler check added to the ACPI video driver back to the core. A mechanism for adding CMOS RTC address space handlers is introduced by Lan Tianyu to allow some EC-related breakage to be fixed on some systems. A spec-compliant implementation of acpi_os_get_timer() is added by Mika Westerberg. The evaluation of _STA is added to do_acpi_find_child() to avoid situations in which a pointer to a disabled device object is returned instead of an enabled one with the same _ADR value. From Jeff Wu. Intel BayTrail PCH (Platform Controller Hub) support is added to the ACPI driver for Intel Low-Power Subsystems (LPSS) and that driver is modified to work around a couple of known BIOS issues. Changes from Mika Westerberg and Heikki Krogerus. The EC driver is fixed by Vasiliy Kulikov to use get_user() and put_user() instead of dereferencing user space pointers blindly. Code cleanups are made by Bjorn Helgaas, Nicholas Mazzuca and Toshi Kani. - Assorted power management updates The "runtime idle" helper routine is changed to take the return values of the callbacks executed by it into account and to call rpm_suspend() if they return 0, which allows us to reduce the overall code bloat a bit (by dropping some code that's not necessary any more after that modification). The runtime PM documentation is updated by Alan Stern (to reflect the "runtime idle" behavior change). New trace points for PM QoS are added by Sahara (<keun-o.park@windriver.com>). PM QoS documentation is updated by Lan Tianyu. Code cleanups are made and minor issues are addressed by Bernie Thompson, Bjorn Helgaas, Julius Werner, and Shuah Khan. - devfreq updates New driver for the Exynos5-bus device from Abhilash Kesavan. Minor cleanups, fixes and MAINTAINERS update from MyungJoo Ham, Abhilash Kesavan, Paul Bolle, Rajagopal Venkat, and Wei Yongjun. - OMAP power management updates Adaptive Voltage Scaling (AVS) SmartReflex voltage control driver updates from Andrii Tseglytskyi and Nishanth Menon." * tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits) cpufreq: Fix cpufreq regression after suspend/resume ACPI / PM: Fix possible NULL pointer deref in acpi_pm_device_sleep_state() PM / Sleep: Warn about system time after resume with pm_trace cpufreq: don't leave stale policy pointer in cdbs->cur_policy acpi-cpufreq: Add new sysfs attribute freqdomain_cpus cpufreq: make sure frequency transitions are serialized ACPI: implement acpi_os_get_timer() according the spec ACPI / EC: Add HP Folio 13 to ec_dmi_table in order to skip DSDT scan ACPI: Add CMOS RTC Operation Region handler support ACPI / processor: Drop unused variable from processor_perflib.c cpufreq: tegra: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: s3c64xx: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: omap: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: imx6q: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: exynos: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: dbx500: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: davinci: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: arm-big-little: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: powernow-k8: call CPUFREQ_POSTCHANGE notfier in error cases cpufreq: pcc: call CPUFREQ_POSTCHANGE notfier in error cases ...
2013-07-03Merge tag 'soc-for-linus' of ↵Linus Torvalds1-14/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC specific changes from Arnd Bergmann: "These changes are all to SoC-specific code, a total of 33 branches on 17 platforms were pulled into this. Like last time, Renesas sh-mobile is now the platform with the most changes, followed by OMAP and EXYNOS. Two new platforms, TI Keystone and Rockchips RK3xxx are added in this branch, both containing almost no platform specific code at all, since they are using generic subsystem interfaces for clocks, pinctrl, interrupts etc. The device drivers are getting merged through the respective subsystem maintainer trees. One more SoC (u300) is now multiplatform capable and several others (shmobile, exynos, msm, integrator, kirkwood, clps711x) are moving towards that goal with this series but need more work. Also noteworthy is the work on PCI here, which is traditionally part of the SoC specific code. With the changes done by Thomas Petazzoni, we can now more easily have PCI host controller drivers as loadable modules and keep them separate from the platform code in drivers/pci/host. This has already led to the discovery that three platforms (exynos, spear and imx) are actually using an identical PCIe host controller and will be able to share a driver once support for spear and imx is added." * tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (480 commits) ARM: integrator: let pciv3 use mem/premem from device tree ARM: integrator: set local side PCI addresses right ARM: dts: Add pcie controller node for exynos5440-ssdk5440 ARM: dts: Add pcie controller node for Samsung EXYNOS5440 SoC ARM: EXYNOS: Enable PCIe support for Exynos5440 pci: Add PCIe driver for Samsung Exynos ARM: OMAP5: voltagedomain data: remove temporary OMAP4 voltage data ARM: keystone: Move CPU bringup code to dedicated asm file ARM: multiplatform: always pick one CPU type ARM: imx: select syscon for IMX6SL ARM: keystone: select ARM_ERRATA_798181 only for SMP ARM: imx: Synertronixx scb9328 needs to select SOC_IMX1 ARM: OMAP2+: AM43x: resolve SMP related build error dmaengine: edma: enable build for AM33XX ARM: edma: Add EDMA crossbar event mux support ARM: edma: Add DT and runtime PM support to the private EDMA API dmaengine: edma: Add TI EDMA device tree binding arm: add basic support for Rockchip RK3066a boards arm: add debug uarts for rockchip rk29xx and rk3xxx series arm: Add basic clocks for Rockchip rk3066a SoCs ...
2013-06-24cpuidle: calxeda: select ARM_CPU_SUSPENDArnd Bergmann1-0/+1
Like other ARM specific drivers, this one requires ARM_CPU_SUSPEND, as shown by this linker error: drivers/built-in.o: In function `calxeda_pwrdown_idle': drivers/cpuidle/cpuidle-calxeda.c:84: undefined reference to `cpu_suspend' drivers/cpuidle/cpuidle-calxeda.c:86: undefined reference to `cpu_resume' Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-pm@vger.kernel.org
2013-06-11cpuidle: Fix ARCH_NEEDS_CPU_IDLE_COUPLED dependency warningDaniel Lezcano1-3/+3
Before commit d6f346f (cpuidle: improve governor Kconfig options), the CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED option didn't depend on CONFIG_CPU_IDLE but now it has been moved under the CPU_IDLE menuconfig. That raises the following warnings: warning: (ARCH_OMAP4 && ARCH_TEGRA_2x_SOC) selects ARCH_NEEDS_CPU_IDLE_COUPLED which has unmet direct dependencies (CPU_IDLE) warning: (ARCH_OMAP4 && ARCH_TEGRA_2x_SOC) selects ARCH_NEEDS_CPU_IDLE_COUPLED which has unmet direct dependencies (CPU_IDLE) because the tegra2 and omap4 Kconfig files select this option without checking if CPU_IDLE is set. Fix that by moving ARCH_NEEDS_CPU_IDLE_COUPLED outside of CPU_IDLE. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-11cpuidle: Comment the driver's framework codeDaniel Lezcano1-6/+126
Add kerneldoc (and other) comments to the cpuidle driver's framework code. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-11cpuidle: simplify multiple driver supportDaniel Lezcano2-115/+81
Commit bf4d1b5 (cpuidle: support multiple drivers) introduced support for using multiple cpuidle drivers at the same time. It added a couple of new APIs to register the driver per CPU, but that led to some unnecessary code complexity related to the kernel config options deciding whether or not the multiple driver support is enabled. The code has to work as it did before when the multiple driver support is not enabled and the multiple driver support has to be compatible with the previously existing API. Remove the new API, not used by any driver in the tree yet (but needed for the HMP cpuidle drivers that will be submitted soon), and add a new cpumask pointer to the cpuidle driver structure that will point to the mask of CPUs handled by the given driver. That will allow the cpuidle_[un]register_driver() API to be used for the multiple driver support along with the cpuidle_[un]register() functions added recently. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-05ARM: zynq: Add cpuidle supportMichal Simek3-0/+91
Add cpuidle support for Xilinx Zynq. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-03cpuidle: improve governor Kconfig optionsDaniel Lezcano1-9/+7
Each governor is suitable for different kernel configurations: the menu governor suits better for a tickless system, while the ladder governor fits better for a periodic timer tick system. The Kconfig does not allow to [un]select a governor, thus both are compiled in the kernel but the init order makes the menu governor to be the last one to be registered, so becoming the default. The only way to switch back to the ladder governor is to enable the sysfs governor switch in the kernel command line. Because it seems nobody complained about this, the menu governor is used by default most of the time on the system, having both governors is not really necessary on a tickless system but there isn't a config option to disable one or another governor. Create a submenu for cpuidle and add a label for each governor, so we can see the option in the menu config and enable/disable it. The governors will be enabled depending on the CONFIG_NO_HZ option: - If CONFIG_NO_HZ is set, then the menu governor is selected and the ladder governor is optional, defaulting to 'yes' - If CONFIG_NO_HZ is not set, then the ladder governor is selected and the menu governor is optional, defaulting to 'yes' Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-29ARM: introduce common set_auxcr/get_auxcr functionsRob Herring1-14/+0
Move the private set_auxcr/get_auxcr functions from drivers/cpuidle/cpuidle-calxeda.c so they can be used across platforms. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: Will Deacon <will.deacon@arm.com>
2013-04-27cpuidle: add maintainer entryDaniel Lezcano2-3/+6
Currently cpuidle drivers are spread across different archs. As a result, there are several different paths for cpuidle patch submissions: cpuidle core changes go through linux-pm, ARM driver changes go to the arm-soc or SoC-specific trees, sh changes go through the sh arch tree, pseries changes go through the PowerPC tree and finally intel changes go through the Len's tree while ACPI idle changes go through linux-pm. That makes it difficult to consolidate code and to propagate modifications from the cpuidle core to the different drivers. Hopefully, a movement has started to put the majority of cpuidle drivers under drivers/cpuidle like cpuidle-calxeda.c and cpuidle-kirkwood.c. Add a maintainer entry for cpuidle to MAINTAINERS to clarify the situation and to indicate to new cpuidle driver authors that those drivers should not go into arch-specific directories. The upstreaming process is unchanged: Rafael takes patches for merging into his tree, but with an Acked-by: tag from the driver's maintainer, so indicate in the drivers' headers who maintains them. The arrangement will be the same as for cpufreq. [rjw: Changelog] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andrew Lunn <andrew@lunn.ch> #for kirkwood Acked-by: Jason Cooper <jason@lakedaemon.net> #for kirkwood Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-24cpuidle: fix comment formatDaniel Lezcano1-1/+1
Fix comment format for the kernel doc script. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-23ARM: kirkwood: cpuidle: use init/exit common routineDaniel Lezcano1-15/+2
Remove the duplicated code and use the cpuidle common code for initialization. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Tested-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-23ARM: calxeda: cpuidle: use init/exit common routineDaniel Lezcano1-51/+1
Remove the duplicated code and use the cpuidle common code for initialization. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-23cpuidle: make a single register function for allDaniel Lezcano1-0/+72
The usual scheme to initialize a cpuidle driver on a SMP is: cpuidle_register_driver(drv); for_each_possible_cpu(cpu) { device = &per_cpu(cpuidle_dev, cpu); cpuidle_register_device(device); } This code is duplicated in each cpuidle driver. On UP systems, it is done this way: cpuidle_register_driver(drv); device = &per_cpu(cpuidle_dev, cpu); cpuidle_register_device(device); On UP, the macro 'for_each_cpu' does one iteration: #define for_each_cpu(cpu, mask) \ for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) Hence, the initialization loop is the same for UP than SMP. Beside, we saw different bugs / mis-initialization / return code unchecked in the different drivers, the code is duplicated including bugs. After fixing all these ones, it appears the initialization pattern is the same for everyone. Please note, some drivers are doing dev->state_count = drv->state_count. This is not necessary because it is done by the cpuidle_enable_device function in the cpuidle framework. This is true, until you have the same states for all your devices. Otherwise, the 'low level' API should be used instead with the specific initialization for the driver. Let's add a wrapper function doing this initialization with a cpumask parameter for the coupled idle states and use it for all the drivers. That will save a lot of LOC, consolidate the code, and the modifications in the future could be done in a single place. Another benefit is the consolidation of the cpuidle_device variable which is now in the cpuidle framework and no longer spread accross the different arch specific drivers. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-23cpuidle: remove en_core_tk_irqen flagDaniel Lezcano3-56/+18
The en_core_tk_irqen flag is set in all the cpuidle driver which means it is not necessary to specify this flag. Remove the flag and the code related to it. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org> # for mach-omap2/* Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpuidle: initialize the broadcast timer frameworkDaniel Lezcano1-2/+29
The commit 89878baa73f0f1c679355006bd8632e5d78f96c2 introduced the CPUIDLE_FLAG_TIMER_STOP flag where we specify a specific idle state stops the local timer. Now use this flag to check at init time if one state will need the broadcast timer and, in this case, setup the broadcast timer framework. That prevents multiple code duplication in the drivers. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpuidle: kirkwood: fix coccicheck warningsSilviu-Mihai Popescu1-3/+3
Convert all uses of devm_request_and_ioremap() to the newly introduced devm_ioremap_resource() which provides more consistent error handling. devm_ioremap_resource() provides its own error messages so all explicit error messages can be removed from the failure code paths. Signed-off-by: Silviu-Mihai Popescu <silviupopescu1990@gmail.com> Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpuidle / kirkwood: remove redundant Kconfig optionDaniel Lezcano2-7/+1
When the CPU_IDLE and the ARCH_KIRKWOOD options are set it is pointless to define a new option CPU_IDLE_KIRKWOOD because it is redundant. The Makefile drivers directory contains a condition to compile the cpuidle drivers: obj-$(CONFIG_CPU_IDLE) += cpuidle/ Hence, if CPU_IDLE is not set we won't enter this directory. This patch removes the useless Kconfig option and replaces the condition in the Makefile by CONFIG_ARCH_KIRKWOOD. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpuidle : handle clockevent notify from the cpuidle frameworkDaniel Lezcano1-0/+9
When a cpu enters a deep idle state, the local timers are stopped and the time framework falls back to the timer device used as a broadcast timer. The different cpuidle drivers are calling clockevents_notify ENTER/EXIT when the idle state stops the local timer. Add a new flag CPUIDLE_FLAG_TIMER_STOP which can be set by the cpuidle drivers. If the flag is set, the cpuidle core code takes care of the notification on behalf of the driver to avoid pointless code duplication. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-22Merge tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds3-0/+113
Pull ARM SoC-specific updates from Arnd Bergmann: "This is a larger set of new functionality for the existing SoC families, including: - vt8500 gains support for new CPU cores, notably the Cortex-A9 based wm8850 - prima2 gains support for the "marco" SoC family, its SMP based cousin - tegra gains support for the new Tegra4 (Tegra114) family - socfpga now supports a newer version of the hardware including SMP - i.mx31 and bcm2835 are now using DT probing for their clocks - lots of updates for sh-mobile - OMAP updates for clocks, power management and USB - i.mx6q and tegra now support cpuidle - kirkwood now supports PCIe hot plugging - tegra clock support is updated - tegra USB PHY probing gets implemented diffently" * tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (148 commits) ARM: prima2: remove duplicate v7_invalidate_l1 ARM: shmobile: r8a7779: Correct TMU clock support again ARM: prima2: fix __init section for cpu hotplug ARM: OMAP: Consolidate OMAP USB-HS platform data (part 3/3) ARM: OMAP: Consolidate OMAP USB-HS platform data (part 1/3) arm: socfpga: Add SMP support for actual socfpga harware arm: Add v7_invalidate_l1 to cache-v7.S arm: socfpga: Add entries to enable make dtbs socfpga arm: socfpga: Add new device tree source for actual socfpga HW ARM: tegra: sort Kconfig selects for Tegra114 ARM: tegra: enable ARCH_REQUIRE_GPIOLIB for Tegra114 ARM: tegra: Fix build error w/ ARCH_TEGRA_114_SOC w/o ARCH_TEGRA_3x_SOC ARM: tegra: Fix build error for gic update ARM: tegra: remove empty tegra_smp_init_cpus() ARM: shmobile: Register ARM architected timer ARM: MARCO: fix the build issue due to gic-vic-to-irqchip move ARM: shmobile: r8a7779: Correct TMU clock support ARM: mxs_defconfig: Select CONFIG_DEVTMPFS_MOUNT ARM: mxs: decrease mxs_clockevent_device.min_delta_ns to 2 clock cycles ARM: mxs: use apbx bus clock to drive the timers on timrotv2 ...
2013-01-31cpuidle: kirkwood: Move out of mach directoryAndrew Lunn3-0/+113
Move the Kirkwood cpuidle driver out of arch/arm/mach-kirkwood and into drivers/cpuidle. Convert the driver into a platform driver. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2013-01-26PM / tracing: remove deprecated power trace APIPaul Gortmaker1-2/+0
The text in Documentation said it would be removed in 2.6.41; the text in the Kconfig said removal in the 3.1 release. Either way you look at it, we are well past both, so push it off a cliff. Note that the POWER_CSTATE and the POWER_PSTATE are part of the legacy tracing API. Remove all tracepoints which use these flags. As can be seen from context, most already have a trace entry via trace_cpu_idle anyways. Also, the cpufreq/cpufreq.c PSTATE one is actually unpaired, as compared to the CSTATE ones which all have a clear start/stop. As part of this, the trace_power_frequency also becomes orphaned, so it too is deleted. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-15cpuidle: remove the power_specified field in the driverDaniel Lezcano3-44/+6
We realized that the power usage field is never filled and when it is filled for tegra, the power_specified flag is not set causing all of these values to be reset when the driver is initialized with set_power_state(). However, the power_specified flag can be simply removed under the assumption that the states are always backward sorted, which is the case with the current code. This change allows the menu governor select function and the cpuidle_play_dead() to be simplified. Moreover, the set_power_states() function can removed as it does not make sense any more. Drop the power_specified flag from struct cpuidle_driver and make the related changes as described above. As a consequence, this also fixes the bug where on the dynamic C-states system, the power fields are not initialized. [rjw: Changelog] References: https://bugzilla.kernel.org/show_bug.cgi?id=42870 References: https://bugzilla.kernel.org/show_bug.cgi?id=43349 References: https://lkml.org/lkml/2012/10/16/518 Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>